{
  description = "Healthchecks";

  inputs = {
    nixpkgs = {
      url = "nixpkgs/nixos-unstable-small";
    };
  };

  outputs = {
    self,
    nixpkgs,
  }: let
    system = "x86_64-linux";
    pkgs = import nixpkgs {
      inherit system;
    };
    py = pkgs.python312.override {
      packageOverrides = final: prev: {
        django = prev.django_5;
      };
    };
    baseImage = {
      tag = "latest";
      maxLayers = 2;
      contents = [
        pkgs.bash
        pkgs.coreutils-full
      ];
      config = {
        User = "5000:5000";
        Volumes = {
          "/tmp" = {};
        };
        WorkingDir = "${self.packages.${system}.healthchecks}/app";
        Env = [
          "LANG=en_US.UTF-8"
          "PYTHONPATH=${self.packages.${system}.healthchecks.pythonPath}"
          "PYTHONUNBUFFERED=1"
          "SSL_CERT_FILE=${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt"
          "STATIC_ROOT=${self.packages.${system}.healthchecks.static}"
        ];
      };
    };
  in {
    packages.${system} = {
      healthchecks = let
        pname = "healthchecks";
        version = "3.6";
        hash = "sha256-aKt9L3ZgZ8HffcNNJaR+hAI38raWuLp2q/6+rvkl2pM=";
        secrets = [
          "DB_PASSWORD"
          "DISCORD_CLIENT_SECRET"
          "EMAIL_HOST_PASSWORD"
          "LINENOTIFY_CLIENT_SECRET"
          "MATRIX_ACCESS_TOKEN"
          "PD_APP_ID"
          "PUSHBULLET_CLIENT_SECRET"
          "PUSHOVER_API_TOKEN"
          "S3_SECRET_KEY"
          "SECRET_KEY"
          "SLACK_CLIENT_SECRET"
          "TELEGRAM_TOKEN"
          "TRELLO_APP_KEY"
          "TWILIO_AUTH"
        ];
        localSettings = pkgs.writeText "local_settings.py" ''
          import os
          CSRF_TRUSTED_HOSTS = os.getenv("CSRF_TRUSTED_HOSTS", "").split(",")
          STATIC_ROOT = os.getenv("STATIC_ROOT")
          STATICFILES_DIRS = [ ]
          ${pkgs.lib.concatLines (map
            (secret: ''
              ${secret}_FILE = os.getenv("${secret}_FILE")
              if ${secret}_FILE:
                  with open(${secret}_FILE, "r") as file:
                      ${secret} = file.readline()
            '')
            secrets)}
        '';
        propagatedBuildInputs = with py.pkgs; [
          aiosmtpd
          apprise
          cronsim
          django
          django-compressor
          django-stubs-ext
          fido2
          minio
          oncalendar
          psycopg2
          pycurl
          pydantic
          pyotp
          segno
          statsd
          whitenoise
        ];
      in
        py.pkgs.buildPythonApplication {
          inherit pname version;
          format = "other";

          outputs = ["out" "static" "doc"];

          src = pkgs.fetchFromGitHub {
            owner = "healthchecks";
            repo = pname;
            rev = "refs/tags/v${version}";
            hash = hash;
          };

          inherit propagatedBuildInputs;

          dontPatch = true;
          dontConfigure = true;
          dontBuild = true;
          doCheck = false;

          installPhase = ''
            mkdir -p $out/app
            cp -r CHANGELOG.md hc manage.py templates $out/app
            chmod +x $out/app/manage.py

            mkdir -p $doc
            cp -r *.md LICENSE $doc

            mkdir -p $static
            DEBUG=False SECRET_KEY=build-key STATIC_ROOT=$static ${py}/bin/python ./manage.py collectstatic --noinput
            DEBUG=False SECRET_KEY=build-key STATIC_ROOT=$static ${py}/bin/python ./manage.py compress
            cp -r static-collected/* $static

            cp ${localSettings} $out/app/hc/local_settings.py
          '';

          passthru = {
            # PYTHONPATH of all dependencies used by the package
            pythonPath = py.pkgs.makePythonPath propagatedBuildInputs;

            tests = {
              inherit (pkgs.nixosTests) healthchecks;
            };
          };

          meta = with pkgs.lib; {
            homepage = "https://github.com/healthchecks/healthchecks";
            description = "A cron monitoring tool written in Python & Django ";
            license = licenses.bsd3;
          };
        };

      smtpd = pkgs.dockerTools.buildLayeredImage (
        pkgs.lib.attrsets.recursiveUpdate baseImage {
          name = "healthchecks-smtpd";
          config = {
            Cmd = [
              "${self.packages.${system}.healthchecks}/app/manage.py"
              "smtpd"
              "--port"
              "2525"
            ];
            ExposedPorts = {
              "2525/tcp" = {};
            };
          };
        }
      );

      sendalerts = pkgs.dockerTools.buildLayeredImage (
        pkgs.lib.attrsets.recursiveUpdate baseImage {
          name = "healthchecks-sendalerts";
          config = {
            Cmd = [
              "${self.packages.${system}.healthchecks}/app/manage.py"
              "sendalerts"
            ];
            ExposedPorts = {};
          };
        }
      );

      sendreports = pkgs.dockerTools.buildLayeredImage (
        pkgs.lib.attrsets.recursiveUpdate baseImage {
          name = "healthchecks-sendreports";
          config = {
            Cmd = [
              "${self.packages.${system}.healthchecks}/app/manage.py"
              "sendreports"
              "--loop"
            ];
            ExposedPorts = {};
          };
        }
      );

      maintenance = let
        script = pkgs.writeTextFile {
          name = "maintenance";
          text = pkgs.lib.concatStringsSep "\n" [
            "#!${pkgs.nushell}/bin/nu"
            ""
            "alias manage = ${self.packages.${system}.healthchecks}/app/manage.py"
            ""
            (builtins.readFile ./maintenance.nu)
          ];
          executable = true;
          destination = "/bin/maintenance";
        };
      in
        pkgs.dockerTools.buildLayeredImage (
          pkgs.lib.attrsets.recursiveUpdate baseImage {
            name = "healthchecks-maintenance";
            config = {
              Cmd = [
                "${script}/bin/maintenance"
              ];
              ExposedPorts = {};
            };
          }
        );

      migrate = pkgs.dockerTools.buildLayeredImage (
        pkgs.lib.attrsets.recursiveUpdate baseImage {
          name = "healthchecks-migrate";
          config = {
            Cmd = [
              "${self.packages.${system}.healthchecks}/app/manage.py"
              "migrate"
            ];
            ExposedPorts = {};
          };
        }
      );

      webserver = let
        uwsgi = pkgs.uwsgi.override {
          plugins = ["python3"];
        };
        uwsgi-ini = pkgs.writeTextFile {
          name = "uwsgi.ini";
          text = ''
            [uwsgi]
            buffer-size = 32768
            chdir = ${self.packages.${system}.healthchecks}/app
            die-on-term
            disable-write-exception
            enable-threads
            harakiri = 10
            http-socket = :8000
            master
            max-fd = 10000
            mime-file = ${pkgs.mailcap}/etc/nginx/mime.types
            module = hc.wsgi:application
            plugins = python3
            post-buffering = 16192
            processes = 4
            threads = 1
            thunder-lock
          '';
        };
      in
        pkgs.dockerTools.buildLayeredImage (
          pkgs.lib.attrsets.recursiveUpdate baseImage {
            name = "healthchecks-webserver";
            fakeRootCommands = ''
              mkdir /tmp
              chmod 0777 /tmp
            '';
            config = {
              Cmd = [
                "${uwsgi}/bin/uwsgi"
                "${uwsgi-ini}"
              ];
              ExposedPorts = {
                "8000/tcp" = {};
              };
            };
          }
        );

      static = pkgs.dockerTools.buildLayeredImage {
        name = "healthchecks-static";
        tag = "latest";
        maxLayers = 2;
        config = {
          User = "5000:5000";
          Cmd = [
            "${pkgs.static-web-server}/bin/static-web-server"
            "--port=8000"
            "--root=${self.packages.${system}.healthchecks.static}"
          ];
          ExposedPorts = {
            "8000/tcp" = {};
          };
        };
      };
    };
    checks.${system} = {
      webserver = self.packages.${system}.webserver;
      smtpd = self.packages.${system}.smtpd;
      sendalerts = self.packages.${system}.sendalerts;
      sendreports = self.packages.${system}.sendreports;
      maintenance = self.packages.${system}.maintenance;
      migrate = self.packages.${system}.migrate;
      static = self.packages.${system}.static;
    };
  };
}